Coraciiformes Taxon Advisory Group -

General Information

This
species occurs singly or in pairs (Williams, 1978), is very territorial,
vocal, and can be aggressive. When feeding, the bird will swoop down from
a perch to catch its prey on the ground. After catching the prey it will
remain at the kill site while eating or may return to the perch where
it will beat the prey against a branch before consuming the carcass.

The
"rolling" for which the bird receives its name, is a territorial
advertisement. This behavior is usually performed after copulation, against
intruders, or to draw attention away from a nest or chickes (Fry, 1988).
The behavior involves the bird flying strongly upwards for about 30 feet,
then tipping forward and falling with closed wings. The bird plummets,
picking up speed, occasionally flapping its wings to gain even more speed.
It then levels its flight, rolls to the right and then the left. It will
do this five or six times in a matter of seconds (Fry, 1992). The bird
may then sweep upward, close its wings and lose speed until it tips forward
into a repeat of the roll sequence. Calling is also done while the bird
is performing the rolls.

Description

Status

Considered
common, the population is at its greatest density in easy Kenya with as
many as 26 birds being counted on a 250 km stretch of road in late April.
Abundant in Somalia, frequent to common in Ethiopia, common in the rest
of East Africa (Fry, 1988).

Range

Habitat

This
roller inhabits Acacia savannas with well-spaced trees and brushlands
(Fry, 1992). It can be found in open bush country where isolated trees
serve as vantage points (Williams, 1978). Also occurs in lightly forested
areas including cultivated lands and large gardens (Fry, 1988), although
it does not associate closely with human habitation (Fry, 1992).

Vocalizations

The
call, in flight and while perched, is a loud guttural "rak, rak".
While performing the rolling flight display, this call is rapidly repeated
and leads into a harsh, loud "kaaa, kaarsh, kaaaarrsh" call
(Fry, 1992).

Reproduction

In
the wild, nests are recorded as being eight to fifteen feet above the
ground in a decayed tree branch stump or the top of a dead palm (Fry,
1988). Nests have also been recorded in the sides of termite mounds (Fry,
1992). A pair will modify a nest, but they will not excavate the cavity.
But for a few leaf fragments, the nest is unlined (Fry, 1988).

Throughout
its range, this roller has been recorded as nesting in all months of the
year. The main nesting season is in October and November. Two to four
glossy, smooth, pure-white eggs are laid and incubated by both the male
and the female. Chicks hatch after an incubation period of 22 to 24 days.